Job 1: Develop energy know-how
News index...Alternative fuels pose complex science, engineering challenges.
Burning switchgrass to generate electricity isn't as simple as it sounds. You can't just pitch dried grass into a furnace.
Several engineering innovations had to be made to conduct switchgrass-burning tests at Alliant Energy's Ottumwa Generating Station. They included devising machinery that is capable of processing switchgrass into small particles that can be blown through a pipe into a 1,800-degree furnace. There, suspended in air, the particles burn along with pulverized coal. The burning heats a boiler to produce steam, which powers the giant turbines that make the electricity.
The machinery feeding switchgrass into the furnace must be automatic and work continuously for hundreds of hours without a break.
Using switchgrass as a renewable fuel might be a down-to-earth idea, but it's definitely not a low-tech undertaking. The same is true of all the emerging alternative-energy technologies, whether they involve producing electricity or motor fuels, whether they start as plant materials or animal waste or wind.
All are simple ideas that require complex science and engineering to make them work. All are in their formative stages, and none will realize its potential without more research, experimentation and demonstration.
That's why it is critical that state policymakers, in their desire to foster renewable-energy industries in Iowa, must concentrate first and foremost on research. Above all, the state universities must be supported at a level that assures this state will be one of the places the world turns for know-how on alternative fuels.
The switchgrass project in southern Iowa illustrates the complexity. The federally funded project was undertaken by a multicounty development group, Chariton Valley Resource Conservation and Development, in cooperation with Alliant Energy and several other partners. The project is testing the possibilities of co-firing a generating plant with coal and switchgrass.
The potential gains are many. For the power company, co-firing with switchgrass reduces emissions of sulfur, and switchgrass makes no net addition of greenhouse gas to the atmosphere. For the local economy, it means keeping some money here instead of shipping it to Wyoming to buy coal.
Switchgrass has about two-thirds the energy content of coal. It can be grown on marginal land, giving farmers a potential new crop without reducing regular crop production. It has a deep root system, which can stop erosion and help clean up lakes and streams. It shelters wildlife.
In addition to use in co-firing, switchgrass is seen as a potentially better feedstock than corn for ethanol production, and it is being investigated as a possible source of hydrogen.
There is nothing not to like about switchgrass. It could be Iowa's long-dreamed-of third major crop, after corn and soybeans.
The trick will be to make switchgrass economically viable as an energy crop, which will be the next phase of the Chariton Valley project. Achieving viability will involve improvements in every step along the way: finding the right plant varieties for maximum yield, developing the best management practices, finding more cost-effective means of harvest, transportation and storage and improving the machinery for processing the grass into fuel.
Every step will involve science and engineering.
It's worth saying again: If Iowa is going to cash in on its vast potential in alternative energy, the key is to support research at the state universities and at projects like Chariton Valley.
If the best research is done in Iowa, the state will have a big future in alternative energy, be it from switchgrass or some other source that hasn't yet been imagined.
Originally published in the Des Moines Register June 25, 2006